In classic latch-type firing mechanisms, the firing lever is provided with a latch element that engages with a complementary latch element of a trigger plate in the cocked position. When a shot is fired with such a latch-type firing mechanism, the latch elements are disengaged and the trigger elements are separated from one another. This means that another spring needs to be provided in addition to the trigger spring in order to cock the firing mechanism anew. This additional spring presses the trigger lever and the firing sear back into their engaged starting position. Under extreme conditions such as, for example, significant soiling, gumming or icing, it may occur, however, that individual elements of the firing mechanism are not returned to their starting positions after a shot is fired. This prevents the breech lock from being cocked anew and therefore makes it impossible to fire another shot. Under the aforementioned extreme conditions, there is also a certain risk of the firing sear of conventional latch-type firing mechanisms remaining in its position and not releasing the firing pin after a shot is fired.
In a firing mechanism known from DE 93 10 821 U, these problems are prevented by coupling the trigger elements to one another with the aid of a toggle link mechanism. This is achieved by providing a link that is coupled to the trigger plate on one side and to a first lever arm of an articulated lever that is pivotable about a fulcrum pin on the other side. The second lever arm of the articulated lever is connected in an articulated fashion to the lower end of a trigger rod that can be moved in the axial direction. This resulted in an engagement-free forcible connection between the trigger and the trigger rod that also made it possible to manually reset the firing mechanism. However, the resistance of the trigger cannot be easily adjusted in such a firing mechanism.
The invention is based on the objective of developing a firing mechanism of the initially described type that also makes it possible to easily change the resistance of the trigger without requiring significant constructive modifications.
This objective is attained with a firing mechanism as set forth herein. Practical embodiments and advantageous additional developments of the invention are characterized in the dependent claims.